Evaluation of the Sceptor microdilution antibiotic susceptibility testing system: a collaborative investigation.
A multiwell, dried antimicrobial agent susceptibility test system, Sceptor (BBL Microbiology Systems, Cockeysville, Md.), was tested. The system was compared directly with a reference microdilution method by using two collections of stock cultures and 305 fresh clinical isolates. Sceptor was found to be in agreement (+/- log2 dilution) with the reference microdilution method in 96.9 to 98.3% of 9,840 minimal inhibitory concentration determinations performed on stock strains and 95.0% of 7,308 minimal inhibitory concentrations obtained from the clinical isolates. The intralaboratory and interlaboratory reproducibility on stock strains was 97.6 and 97.2%, respectively. The intralaboratory reproducibility for the clinical isolates was 96.9%. Sceptor accurately categorized representative challenge strains of methicillin-resistant staphylococci, beta-lactamase-producing bacteria, organisms producing other antimicrobial agent-inactivating enzymes, and permeability mutants as resistant. Only 0.2% very major errors (false-sensitive minimal inhibitory concentrations by Sceptor) were identified among the clinical isolate test results, the majority being clinically insignificant. The product is accurate and reliable, has a long shelf life, and seems applicable for routine use in clinical laboratories.
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects; D005069:Evaluation Studies as Topic; D008826:Microbial Sensitivity Tests / Q000379:methods*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013210:Staphylococcus / Q000187:drug effects; D013291:Streptococcus / Q000187:drug effects
D000900:Anti-Bacterial Agents